Combining multiple cells into one (without losing data) if the rest of the row is equal

Well, there may be big solutions/ vba code to extract the require data. My way to do this would be, extract the unique car model names and check the lowest and highest year it was made and group the years accordingly ( I have used data-->advance filter to get the unique model names... vlookup and index,sumproduct to get the low and high year based on the model names, which i have done in blad2)

Then, i would apply the grouped years to all data per the model name. CONCATENATE all the columns to remove the duplicates and de CONCATENATE to get back the unique records.(which i have done in blad1).

See if this example way of data extract helps. It's not huge task and can be done in few mins

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